<?php
abstract class STE_Db
{
	protected $_db;
	
	function __construct($db)
	{
		if (($db === null) || (!$db instanceof Zend_Db_Adapter_Abstract))
			throw new Exception("$db must be of type Zend_Db_Adapter_Abstract.");
		
		$this->_db = $db;
	}
}
?>